Advanced Materials Research Vol. 893

Abstract: A new aroylhydrazone compound of 4-hydroxybenzaldehyde benzoyl hydrazone was synthesized through the condensation of 4-hydroxybenzaldehyde and benzoyl hydrazine. The crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group Pbca with a=1.5514(3) nm, b=0.9318(16) nm, c=2.2921(4)nm, β=90.00o, Z=8, V=3.3137(10)nm3. Its crystal structure was determined and refined to a final R=0.0567 for 2725 independent reflections. The intermolecular hydrogen bonding interactions, C-O...N and O-H...O-C, connect the molecules into a layered network structure. The compound showed broad spectrum activity against S. aureus, E. Coli and P. Aeruginosa. The compound has the higher activity for Escherichia coli.

Abstract: Static and dynamic experiments were used to evaluate scale inhibition performance of modified polyaspartic acid (PASP-ASP). The static experiments showed that the PASP-ASP had good scale inhibition performance and the scale inhibition rate exceeded 98% when the PASP-ASP was 2 mg·L^-1 and the solution temperature was 40 ^OC. In the dynamic experiments, almost no scale was formed on the heat transfer surface and the fouling thermal resistance decreases extraordinarily with PASP-ASP treatment experiment compared with the experiment without treatment. The PASP-ASP could be used in industrial cooling water systems.

Abstract: We investigated a novel artificial metamaterial that includes two plates of quartz glass dielectric material and a Ag microstructure sandwiched between the two plates. The Ag grid layer was designed and subsequently prepared by tape casting and screen printing. The transmission characteristics of this metamaterial were able to be controlled by adjusting the geometry parameters of the Ag grid such as the width of the strip and the size of the unit cell. Our work has demonstrated the possibility that the ceramic metamaterial can be used as a transmission material capable of work at high temperatures below the melting point of the metal.

Abstract: The adsorption and doping of Pd atom on graphene have been investigated using density-functional theory. The structure, binding energy, Mulliken population, and density of states of Pd-graphene systems are calculated. For the adsorbed graphene, the bridge site is the most favorable adsorption site. The adsorbed and doped Pd atom can stay stably on graphene by donating their charges to graphene, resulting in the charge redistribution of graphene. After the Pd functionalization, the hybridization of states of Pd and C atoms can be observed, indicating strong interaction between them.

Abstract: In this paper, the effects of the preparation conditions on the combination of the eosin dye and titanium dioxide were researched. The synthesis conditions included the absorption time, the initial dye concentration and the amount of absorbed titanium dioxide. The absorption properties of the eosin dye to the nano materials TiO₂ were examined. The relations of absorption amount Q with the preparation variables had been investigated by analysis to the experimental results. The absorption amount Q decreased with increasing the absorbed TiO₂ amount.

Abstract: The catalytic effect of Brønsted acidic ionic liquid for PET hydrolysis reaction under microwave irradiation has been investigated through orthogonal experiment in this article, and the influence of main reaction conditions has also been studied. The results shown that the influence level sequence of reaction factors was: catalyst kind > reaction time > reaction temperature > catalyst dosage. According to a further study of catalyst dosages influence on PET depolymerization degree, the optimal reaction condition was finally concluded as below: [Hexanemi [HSO₄] used as catalyst, catalyst dosage: 0.01 mol/2 g PET, reaction time: 210 min, reaction temperature: 195 °C.

Abstract: Synthesised PVA/CS/SiO₂ beads had been considered as a promising alternative to conventional means of heavy metal removal. The PVA/CS/SiO₂ beads were successfully synthesised through a simple dropwise method and different ratio of cross-linking agent, glutaraldehyde (GLA) of 0, 0.25M and 0.5M were used to cross-link the PVA/CS/SiO₂ beads. Solubility and swelling behavior of the beads were also investigated within the prescribed time of 24h in three different medium of acidic, distilled water and alkaline solution. Result of solubility test showed that PVA/CS/SiO₂ beads without GLA dissolves in acidic medium but insoluble in distilled water and alkaline solution. Meanwhile, the PVA/CS/SiO₂ beads cross-linked with GLA did not dissolve in all three mediums. The swelling test revealed that PVA/CS/SiO₂ beads without cross-linked with GLA showed the highest of swelling in acidic solution which was 225.2% and PVA/CS/SiO₂ beads cross-linked with 0.5M GLA recorded the lowest of swelling in acidic solution which was 98.6%. This concluded that as the cross-linking ratio increased, the swelling behaviour of the PVA/CS/SiO₂ beads decreased.

Abstract: Photocatalytic hydrogen generation holds promise as the future source of environmentally friendly and economically feasible energy source. In order to conduct more efficient photocatalytic reaction, anatase TiO₂ doped with transition metals is proposed as catalyst. Investigation was conducted by using density functional theory (DFT) augmented with Hubbard U treatment to correct the band gap of TiO₂. Emergence of new states inside the band gap of doped anatase TiO₂ can lead to a material with a better photocatalytic property, i.e., able to work at visible light than that of pristine TiO₂ which is sensitive to UV light only. The investigated materials comply with standard hydrogen electrode (SHE), thus can be used as photocatalyst in water splitting reaction. Out of the two options tested, TiO₂ doped with Fe produces a material with the better photocatalytic properties.Keywords: DFT + U, anatase TiO₂, photocatalytic, water splitting, band gap

Abstract: Theoretical investigation of co-adsorption process between hydrazine (N₂H₄) and OH^- on Ni(111) is performed using density functional theory. OH^- adsorption mechanisms at various adsorption sites as well as its interaction with hydrazine in various conformations (anti, cis, and gauche) are studied. The stability of OH^- adsorption on nickel surface is significantly influenced by the presence of hydrazine molecule. Among the three conformations of hydrazine, OH^- adsorption on nickel surface doesn't occur in cis conformation. Otherwise, co-adsorption occurs in system with gauche and anti conformation. In anti system, hydrazine conformation is transformed during relaxation process and forms gauche conformation as the most stable configuration of the system.